1. Field of the Invention
The present invention relates to a folding structure for carrier's handlebar, particularly to a folding structure for carrier's handlebar in which the movability of the second joint is controlled by whether the occluding teeth on the bottom end of the slider mesh with the positioning teeth of the first joint or not. In this manner, it is convenient for user to adjust the angle of the dragon head handlebar.
2. Brief Description of the Prior Art
Environmental consciousness has been upsurging due to both the soaring high of global oil price and climate abnormality caused by green house effect, thus green energy is becoming the hot issue which attracts close attention from all over the world. Accordingly, the so-called “green transportation revolution” triggered by the manual scooter is spreaded all over the world. After understanding the importance of developing the green transportation, government of each country begins to increase the construction of new bikeway, road or relevant public facilities. Inasmuch as the manual scooter is easy to operate by consumer and can satisfy on-time demand of consumer, the manual scooter industry is no doubt a prospective potential business meeting the requirement of environment protection and energy saving as well as the new momentum of continuing growth for scooter industry. The reasons why consumer will choose manual scooter as the traffic means includes: cheapness on sale price and running cost, solution for parking difficulty and traffic jamming, best solution for LOHAS without car-driving which usually uses petroleum fuel and cause air and noise pollution problem. Therefore, the manual scooter termed as “pioneer of green transportation era” will become the most prospective star industry of tomorrow. According to demand and function, the manual scooter can be divided into: scooter of special purpose carrier for leisure time and industrial use, scooter for vulnerable age people, and scooter of middle and short travel distance for metropolitan.
Most of the abovementioned scooter are provided with a dragon head adjustment structure by which user can adjust the dragon head of the scooter for easy operation and contraction. The dragon head is composed of an upper stem, a lower stem and a trigger, in which the upper stem is provided with a through hole and a fixing hole, the upper end of the lower stem being provided with a receiving frame having an adjusting hole with arc curve shape and a positioning hole being formed at the lower side of the adjusting hole; a spindle having a thread and being in thread engagement with a nut pivotally provided at the acting end of the trigger. In this manner, the upper stem can be put into the receiving frame of the lower stem, and a pin is inserted through the positioning hole and the fixing hole so that the upper stem and the lower stem can be pivotally connected together. Further, a spindle inserted with a washer is inserted through the adjusting hole and the through hole, and then another washer is inserted thereon. A nut is in thread engagement with the spindle such that the upper stem, the lower stem and the trigger can be assembled into an adjusting structure of the dragon head. Then, the turn-up or pull-down action of the trigger is conducted such that the angle of the dragon head can be appropriately adjusted to be fixed in place.
In the practical use of the above dragon head adjusting structure, although the angle of the dragon head is adjusted and fixed in place by the turn-up or pull-down action of the trigger, user often forget to put the pin to fix the trigger. This will cause the easy sliding of the dragon head due to unfixing. In this case, it might be hazardous to user to cause safety problem.